Field of the Invention. The present invention relates to a method of applying a mica paper as insulation to an electrical conductor and a mica paper tape useful in such method.
Description of the Related Art. High mica-content papers are useful as insulation in motors, generators and inverters. Mica papers with higher content mica typically have a mechanical supporting layer such as a glass cloth or polyester film to compensate for mechanical weakness in the mica paper associated with the high mica content. However the mechanical supporting layer is undesirable in use in electrical equipment because many insulation failures are attributable to that mechanical support layer and its lower corona resistance, different thermal expansion, and different conductivity.
It is common to spirally or helically wrap electrical insulation, in the form of a tape, around a conductor using a machine especially designed to maintain the tension on the tape while rapidly wrapping the tape around the conductor. These machines generally require the use of mica paper tapes with a mechanical supporting layer, therefore the mechanical supporting layer with its less than desirable electrical performance becomes a part of the insulation.
Therefore there is a need for a method of successfully wrapping a mica paper around an electrical conductor wherein it is not required to include the mechanical supporting layer in the electrical insulation.